"""Tests for the Small Skill Registry (app/ai/skill_registry.py)."""

from __future__ import annotations

import pytest

from app.ai.skill_registry import SkillDefinition, get_skill_registry


@pytest.fixture(autouse=True)
def _clean_registry():
    """Reset the singleton registry between tests."""
    registry = get_skill_registry()
    for skill in list(registry.list_all()):
        registry.unregister(skill.name)
    yield
    for skill in list(registry.list_all()):
        registry.unregister(skill.name)


def _make_skill(
    name: str = "mail_reader",
    allowed_tool_ids: list[str] | None = None,
    category: str = "general",
) -> SkillDefinition:
    return SkillDefinition(
        name=name,
        description="Read and summarize emails",
        instructions="Use the mail tools to read and summarize emails.",
        allowed_tool_ids=allowed_tool_ids or ["mail_read", "mail_list"],
        context_policy={"include_recent": True},
        category=category,
    )


class TestSkillDefinition:
    def test_defaults(self):
        skill = SkillDefinition(
            name="s", description="d", instructions="i", allowed_tool_ids=["t"]
        )
        assert skill.context_policy is None
        assert skill.category == "general"

    def test_to_dict(self):
        skill = _make_skill()
        data = skill.to_dict()
        assert data["name"] == "mail_reader"
        assert data["allowed_tool_ids"] == ["mail_read", "mail_list"]
        assert data["context_policy"] == {"include_recent": True}
        assert data["category"] == "general"


class TestSkillRegistry:
    def test_register_and_get(self):
        registry = get_skill_registry()
        skill = _make_skill()
        registry.register(skill)
        assert registry.get("mail_reader") is skill

    def test_get_missing_returns_none(self):
        registry = get_skill_registry()
        assert registry.get("nope") is None

    def test_get_by_names_skips_unknown(self):
        registry = get_skill_registry()
        a = _make_skill("a")
        b = _make_skill("b")
        registry.register(a)
        registry.register(b)
        resolved = registry.get_by_names(["a", "b", "missing"])
        assert len(resolved) == 2
        assert {s.name for s in resolved} == {"a", "b"}

    def test_list_all_and_list_for_api(self):
        registry = get_skill_registry()
        registry.register(_make_skill("a"))
        registry.register(_make_skill("b"))
        assert len(registry.list_all()) == 2
        api = registry.list_for_api()
        assert len(api) == 2
        assert all("name" in item and "instructions" in item for item in api)

    def test_unregister(self):
        registry = get_skill_registry()
        registry.register(_make_skill())
        registry.unregister("mail_reader")
        assert registry.get("mail_reader") is None

    def test_register_replaces_existing(self):
        registry = get_skill_registry()
        registry.register(_make_skill("a", allowed_tool_ids=["t1"]))
        registry.register(_make_skill("a", allowed_tool_ids=["t2"]))
        assert registry.get("a").allowed_tool_ids == ["t2"]
        assert len(registry.list_all()) == 1

    def test_singleton(self):
        assert get_skill_registry() is get_skill_registry()